Quantum Mechanics without the math

[Chuckanut]

Ars Technica is publishing a seven part series on Quantum Mechanics for those of us who aren't physicists. I think it will be interesting.

If quantum mechanics hasn’t profoundly shocked you, you haven’t understood it yet. Everything we call real is made of things that cannot be regarded as real. – Niels Bohr

Embarking on a series of quantum mechanics articles can be intimidating. Few things trigger more fear than “a simple introduction to physics.” But to the intrepid and brave, I will make a few promises before we start:

• No math. While the language of quantum mechanics is written using fairly advanced math, I don’t believe one has to read Japanese before you can appreciate Japanese art. Our journey will focus on the beauty of the quantum world.
• No philosophy. There has been a fascination with the ‘meaning’ of quantum mechanics, but we’ll leave that discussion for pints down at the pub. Here we will focus on what we see.
• Everything we encounter will be experimentally verified. While some of the results might be surprising, nothing we encounter will be speculative.

https://arstechnica.com/science/2021/01/the-curious-observers-guide-to-quantum-mechanics/

 

[sengsational]

Razzles is a candy! Razzles is a gum!


"Tea" and "No Tea" at the same time!

 

[Out-to-Lunch]

Thanks for posting this. Looks like a good series. (Disclosure: I am a physicist, and I teach quantum mechanics.)

I like the empirical approach he is taking, in particular, stating that no attempt at philosophy will be made. Most physicists don't worry so much about what it "means." IME, students can get hung up on this to the detriment of learning the material. (In fact, I think you have done a small disservice by introducing the subject with the outdated Bohr quote. I don't know a soul who thinks that, for example, objects exhibiting quantum behavior "cannot be regarded as real.")

Again, thanks for bringing attention to this series.

 

[Markola]

I watched the movie “What the Bleep Do We Know” in the early 2000s, which also attempted to explain QM without math. Takeaway? The Universe is nuttier beyond anything we can grasp and our shared structures for trying to make some rudimentary sense of it are really just “agreements.”

 

[ERD50]

Thanks, I'll check it out. I have to admit to getting lost a few chapters in with Hawking's book,

In a similar vein, I sometimes follow some posts at physics.org, and some of the real physicists there get frustrated when someone tries to explain electricity to a newbie/student using analogies (like the water-pipe analogy). They feel this gets in the way of a real understanding of electricity.

But how far do you go? Is electrons and holes and fields enough? Or do we need to delve into QM?

There was a guy there posting questions about basic circuits, he was an HVAC apprentice. And some of these physicists are going into a deep dive into theory when the guy just wants to understand how a relatively simple relay circuit. If you can follow the loop, you can figure this out, you don't need to know the deep theory. Not anymore than anyone needs to understand that the stoichiometric air–fuel mixture for a gasoline engine is about 14.7:1 (or Li1-xCoO2(s)+x Li+ +xe- -> LiCoO2(s) for you EV fans*) to drive a car competently.

-ERD50

* Please excuse the improper formatting of subscripts and superscripts

 

[Koogie]

For another look at quantum mechanics (and fractal theory) that is even simpler and meant for us back of the class types (raises hand covered in paste) check out the funny and fascinating BBC documentary from 2009:

How long is a piece of string ?

https://www.dailymotion.com/video/x7vipj6


Starring Alan Davies of QI and "Jonathan Creek" fame

 

[stepford]

I think (like a lot of things) one's comfort with QM depends on one's age when introduced to it. By the time I was a freshman physics major 40+ years ago quantum mechanics was a part of the basic curriculum. I had no trouble accepting wave particle duality and all the "spooky" stuff at age 18 and it still doesn't bother me (much).

My Dad was a pretty smart guy, but learned physics in an earlier (pre-WWII) era. He could do the math, but never could get comfortable with the implications of things like observability and wave function collapse. I'm not any smarter than he was. The concepts just hit me when my brain was more plastic.

 

[Lewis Clark]

Einstein never liked quantum mechanics, either. And he even earned a Nobel Prize for his explanation of the photoelectric effect ... which was a major contribution to quantum mechanics.

There will probably not be another time when a scientist earns a Nobel Prize for one of his or her lesser accomplishments.

 

[braumeister]

Einstein never liked quantum mechanics, either. And he even earned a Nobel Prize for his explanation of the photoelectric effect ... which was a major contribution to quantum mechanics.

There will probably not be another time when a scientist earns a Nobel Prize for one of his or her lesser accomplishments.

Einstein's Nobel was an interesting case. I just read about it recently.

It seems the Nobel committee had wanted to award him the prize for relativity for years, but they could never get one crusty committee member to agree. He said that relativity was nonsense and wouldn't budge. By the time of the 1921 prize they were tired of giving it to what some considered lesser contributors, and there was no real agreement for that year.

So they kicked the can down the road and said they would award no prize in 1921, but combine it with the next year and award both in 1922.

Fortunately, a new member of the committee came up with a compromise for 1922. He suggested they award the 1921 prize to Einstein, not for relativity (which most of them wanted) but for his 1905 photoelectric work, and word its citation a bit vaguely. That idea was accepted, and both the 1921 and 1922 prizes were awarded that year. It was purely a fudge, and everyone knew it.

There was some talk, due to the vague wording, that they were leaving the door open for another Nobel prize, but by that time Einstein was disgusted with the whole thing and he never even bothered to appear there to collect the prize.

 

[DaveLeeNC]

Thanks for posting this. Looks like a good series. (Disclosure: I am a physicist, and I teach quantum mechanics.)

I like the empirical approach he is taking, in particular, stating that no attempt at philosophy will be made. Most physicists don't worry so much about what it "means." IME, students can get hung up on this to the detriment of learning the material. (In fact, I think you have done a small disservice by introducing the subject with the outdated Bohr quote. I don't know a soul who thinks that, for example, objects exhibiting quantum behavior "cannot be regarded as real.")

Again, thanks for bringing attention to this series.

Regarding the underlined statement... I thought that they had actually verified the Wigner's Friend scenario where 2 different observers could view the same event (one from a 'system' that is inside the other) and see different and mutually exclusive outcomes. This is different than the (for example) Special Relativity case of different measurements by different observers. In the SR case both observers would agree on the (for example) length of a ruler when observers were both traveling at the same velocity as a ruler.

What am I missing here? Wigner's Friend seems to be a poster child for there not being a single objective (observable) reality.

Thanks.

dave

 

[unclemick]

Circa 1965 I took the then Modern Physics version. I promptly retreated back to Newton and stayed there.

However after 27 years of ER, may consider some light reading.

Heh heh heh - If I think I understand it then I know that I am in deep do do.

 

[grasshopper]

Ms G and I are What the Bleepers, we are having coffee and a discussion of each thought in the articles. Now where is that darn cat?

 

[JoeWras]

Funny this comes up. Yesterday I watched a not-too-well-known Coens brother's movie named "The Serious Man." (Last day on Netflix yesterday.)

Part of the plot revolves around the main character, who is a physics professor, arguing with a student who wants his grade changed to something higher. The student argues he understands the cat, so he should get a high grade. Our protagonist argues he doesn't understand it unless he can do the math.

Later, the protagonist mutters something about the math maybe not mattering.

 

[ls99]

Is Quantum Mechanics attempting to measure infinity?

 

[REWahoo]

Is Quantum Mechanics attempting to measure infinity?

Of course not. Quantum mechanics are the folks who work on your quantum when it needs to be serviced or repaired.

 

[JoeWras]

Of course not. A quantum mechanic is who works on your quantum when it needs to be serviced or repaired.

Yep. Repairs this:

 

[Out-to-Lunch]

Regarding the underlined statement... I thought that they had actually verified the Wigner's Friend scenario where 2 different observers could view the same event (one from a 'system' that is inside the other) and see different and mutually exclusive outcomes. This is different than the (for example) Special Relativity case of different measurements by different observers. In the SR case both observers would agree on the (for example) length of a ruler when observers were both traveling at the same velocity as a ruler.

What am I missing here? Wigner's Friend seems to be a poster child for there not being a single objective (observable) reality.

Thanks.

dave

Well, Dave, I will probably not be of great help here. I should admit that I was unaware of the 2019 and 2020 publications of the Extended Wigner's Friend tests. In briefly looking at it, I cannot shed much light on it. I will need to look more closely. I will say that it seems too early to say if the case is ironclad.

Also, I must confess that I am confused about something: one of the "outs" seems to be that we only need to give up on locality. But I (and most others) had already given up on locality (but not causality). So it appears that I do not understand the Extended Wigner's Friend scenario.

 

[Out-to-Lunch]

Funny this comes up. Yesterday I watched a not-too-well-known Coens brother's movie named "The Serious Man." (Last day on Netflix yesterday.)

Part of the plot revolves around the main character, who is a physics professor, arguing with a student who wants his grade changed to something higher. The student argues he understands the cat, so he should get a high grade. Our protagonist argues he doesn't understand it unless he can do the math.

Later, the protagonist mutters something about the math maybe not mattering.

Nice!

I often cite this movie to my class. One thing that amuses me is the fact that there was a huge lecture hall taking this class. Sure, right!

The other is that in one of his impassioned lectures, the actor makes a math mistake. The camera cuts between a close up of the board (as he is writing) with the incorrect expression, and a zoomed-out view, where the expression is written correctly. It is an easy mistake to make, so I use this anecdote to ward off this mistake in my students.

 

[Koolau]

Heh, heh, just when we have a few folks who really understand quantum mechanics, along comes stuff like dark energy and dark matter. My gut tells me that if the humane race survives another 10,000 years, we'll have kids who can tell you all about quantum mechanics and even dark energy/matter but will not understand some new physical phenomenon or property that we discover. Physics as a science is good for a long time to come. Lots still to discover. Yay!

 

[ls99]

Yeahbut, will they be able to make a call on one of these?

 

[Chuckanut]

Yeahbut, will they be able to make a call on one of these?

What is that? A USB toaster?

 

[W2R]

After seeing this thread title several times, I just had to pop in and say that Quantum Mechanics without the math, sounds a lot like Shakespeare without the English to me.

 

[audreyh1]

What is that? A USB toaster?

Ha ha!

 

[Out-to-Lunch]

After seeing this thread title several times, I just had to pop in and say that Quantum Mechanics without the math, sounds a lot like Shakespeare without the English to me.

While I tend to agree with your sentiments, and have often said as much to various "Physics groupies" we encounter, have you taken a look at the first installment? It does, to my mind, convey some essential elements of QM, and no math was harmed in the making of the movie.

 

[JoeWras]

After seeing this thread title several times, I just had to pop in and say that Quantum Mechanics without the math, sounds a lot like Shakespeare without the English to me.

I'm not so sure some of the Shakespeare I was forced to read was written in English.